Scaffold device for use on ladders and stepladders



J. T. BOYER May 29, 1934.

SCAFFOLD DEVICE FOR USE ON LADDERS AND STEPLADDERS Original Filed Aug. 6, 1950 Patented May 29, 1934 UNITED STATES SCAFFOLD DEVICE FOR USE ON LADDERS AND STEPLADDERS J. Troy Boyer,

Application August 6,

Champaign, Ill.

1930, Serial No. 473,409

Renewed October 27, 1933 3 Claims.

The invention aims to provide an exceptionally simple and inexpensive, yet an efficient and reliable device for use upon a ladder for the purpose of supporting one end of a scalfold plank at a selected position between any two of the steps or rungs of the ladder, enabling placing of the scaifold .board at the most convenient position for the user or users.

A further object is to provide a device of the class described which may be quickly and easily applied or removed, and may be vertically adjusted with speed and ease, to the most advantageous position.

With the foregoing in view, the invention resides in the novel subject matter hereinafter described and claimed, description being accomplished by reference to the accompanying drawmg.

Fig. 1 is a perspective view showing a portion of a step ladder equipped with the invention.

Fig. 2 is a disassembled perspective view of the attachment.

Fig. 3 is an enlarged horizontal sectional view through the attachment, as indicated by line 33 of Fig. 1.

Fig. 4 is a perspective view similar to a portion of Fig. 3 but showing a construction adapted for use on ladders having cylindrical rungs, instead of flat steps.

A preferred construction has been illustrated and will be specifically described, with the understanding however that within the scope of the invention as claimed, variations may be made.

The device embodies two vertically elongated metal plates 1 (Figs. 1 and 3) or two plates such as 1 of Fig. 4. The plates 1 are provided with straight lower edges adapted to rest upon a step S of a ladder, the rear lower corners of said plates being provided with downwardly projecting fingers 2 to engage the rear edge of the step. The lower ends of the plates 1 are also preferably provided with downwardly projecting spurs 3 to penetrate the step S. The plate 1 however is adapted to rest upon a cylindrical ladder rung and is provided with a rung-receiving notch 4 instead of being provided with a finger and a spur.

The front edge of each plate 1 or l is provided with a lateral flange 5 adapted to lie against the front end of a ladder stile S when the plate is disposed at the inner side of said stile, and. the outer edge of each flange 5 is provided with a rearwardly projecting flange 6 to lie against the outer side of the stile S. A thumb screw 7 is threaded outwardly through each plate 1 or 1 near the upper end of the latter to abut the stile S, thereby co-operating with the formations 2 and 3 or the formation 4, in tightly securing the flanged plates to the stiles.

A cross bar 8 preferably formed from telescopic sections 9 and 10, extends between the two supporting plates 1 (or the plates 1), the ends of said bar being connected with said plates. This bar is intended to support one end of a scaffold plank P, and novel provision is preferably made whereby said bar may be adjusted vertically to different positions with respect to its supporting plates 1 or 1*. The extensibility of the bar 8 allows use of the attachment on ladders of various widths.

In the preferred structure, each plate 1 or 1 is provided with a plurality of vertically spaced vertical slots 11, and the ends of the bar 8 are provided with angular vertically elongated tongues 12 which may be passed through any of said slots when the bar 8 and the plates are properly angled: At the juncture of the tongues 12 with the bar 8, downwardly opening notches 13 may well be formed to interlock with the lower ends of the slots 11.

By providing the novel construction shown and described or a substantial equivalent thereof, a device is provided which may be easily and inexpensively manufactured, sold at small cost, quickly and easily applied to a ladder, vertically adjusted to the most desired position for use, and both eflicient and durable. The device may either be left attached to the ladder or may be disconnected therefrom, disassembled and carried in a tool kit or the like.

I claim:

1. A ladder attachment comprising two vertically elongated supports adapted to rest upon a step or rung of a ladder, a cross bar extending between said supports and adapted to support a scaffold board, means for connecting said cross bar with said supports in any of a plurality of vertically spaced positions, and means for securing said supports to the stiles of a ladder. V

2. A ladder attachment comprising two vertically elongated supporting plates adapted to rest upon a step or rung of a ladder, said plates having vertically spaced slots, a plank-supporting cross bar extending between said plates and having angular tongues at its ends receivable in any of said slots, and means for securing said plates to the stiles of a ladder.

3. A ladder attachment comprising two vertically elongated plates for disposition at the inner sides of ladder stiles and adapted to rest upon a step or rung of a ladder, the lower ends of said plates having downwardly projecting rigid means to abut the rear side of the step or rung to hold said ends against forward shifting, the front edges of said plates being provided with laterally projecting rigid means to lie against the front edges of the stiles, a plank supporting cross bar extending between and connected with said plates, and means for securing said plates against the ladder stiles. J. TROY BOYER. 

